Anti-ageing agents - additives to protect against degradation
What are anti-ageing agents?
Antioxidants are additives that are incorporated into rubber and plastic compounds to slow down the deterioration of material properties caused by environmental influences. Without adequate protection, elastomers such as natural rubber (NR), SBR or NBR will lose their elasticity over time, become brittle, discolour or become fragile. The main causes of this ageing are oxygen, ozone, UV radiation, heat and mechanical stress. The dosage and selection of antioxidants for Molded Rubber, Molded Silicone, Plastic Composite Parts, Metal Composite Partsand Fabric Composite Parts must be carried out in such a way that no undesirable side effects such as discolouration, migration or impairment of LABS freedom occur.
What is the function of anti-ageing agents?
Anti-ageing agents work by intercepting or neutralising harmful influences before they can attack the polymer chains. A distinction is made depending on the active principle:
- Antioxidants - prevent or slow down the oxidative decomposition of the Polymer chains through oxygen and heat
- Antiozonants - provide targeted protection against ozone cracking, especially in dynamically stressed Seals and Vibration dampers
- UV stabilisers - absorb or scatter UV radiation to prevent photochemical degradation
- Waxy protective agents - form a protective layer on the surface that reduces the penetration of ozone and oxygen
Where are anti-ageing agents used?
Anti-ageing agents are used in almost all rubber-processing industries: automotive, construction, mechanical engineering, medical technology and aerospace. In Compounds they are specifically matched to the place of use, the media load and the desired service life. Particularly in outdoor applications (e.g. EPDM-roof profiles), at high temperatures (e.g. FKM-Seals in motors) or under constant UV exposure (e.g. silicone rubber (VMQ) in solar technology) they are indispensable.
